1. Technical Field of the Invention
The present invention relates to an electric discharge lamp control unit which is capable of suppressing harmful effects caused by liquid.
2. Description of the Related Art
Conventionally, an art is disclosed in Japanese Patent Application Laid-Open Publication NO. 10-51158 as an electronic control unit which is employed in a control unit of an electric discharge lamp and which is capable of enhancing waterproof property.
The electronic control unit as disclosed in Japanese Patent Application Laid-Open Publication NO. 10-51158 has a case which includes a box and a cover and which houses a circuit board on which electronic components are implemented. A rib which protrudes from the edge section of the cover toward the inner face side of the box when the opening section of the box is covered with the cover is integrally provided, and resin is filled inside the box so that the resin is in contact with the rib. A cord comes out from the casing through an opened portion thereof for connecting the circuit board and the electric discharge lamp, and the casing is attached so that the opening section of the lamp body of the electric discharge lamp corresponds to the opened portion of the cover.
Thus, this enables preventing liquid from intruding into the electronic components and the circuit board which are housed in the case, even if a gap is generated at a joint between the cover and the box and liquid has intruded inside therethrough. This is because the rib of the cover is in contact with the resin in the box at a portion just inside of the gap.
As described above, since the electronic control unit as disclosed in Japanese Patent Application Laid-Open Publication NO. 10-51158 enables preventing liquid from intruding into the electronic components and the circuit board housed in the case, the electronic control unit is also considered to be capable of making the inside of the electric discharge lamp air tight. However, there is a need for providing a rib in the cover, thereby causing a disadvantage in that the size of the electronic control unit increases.